An isochrone map (isochrone plan, isochrone diagram) in science and urban planning is a map showing areas related to isochrones between different points. An isochrone is defined as "a line drawn on a map connecting points at which something occurs or arrives at the same time". Such a map is sometimes termed simply an isochrone. In hydrology and transportation planning isochrone maps are commonly used to depict areas of equal travel time. The term is also used in cardiology as a tool to visually detect abnormalities using body surface distribution.
Isochrone maps have been used in transportation planning since 1972 or earlier. They are commonly used in the UK in connection with development control. Information technology in the 21st century has enabled them to be dynamically generated for use in websites, being used by house hunters wishing to evaluate residential areas.
Isochrone and related maps are used to show the time taken for runoff water within a drainage basin to reach a lake, reservoir or outlet, assuming constant and uniform effective rainfall. An early example of this method was demonstrated by Clark in 1945.
Time-based travel maps can be created for different modes of transportation, e.g. foot, pedal cycle, motor vehicle. Such maps for private motor transport were widely used in a 1972 study into airport accessibility in Hampshire, South East England. At that time, their use was disadvantaged by being time consuming to create.
Isochrone maps can be generated using the Google Maps API and this can be done from arbitrary starting points. The creation of journey time isochrones to airports in Finland has been explained using the GIS software QGIS and pgRouting (an extension of PostGIS).
Journey time websites have been built using mapping technologies and open data. Examples of such sites are Mapumental and Mapnificent. Such sites can be used by house hunters wishing to evaluate residential areas. An isochrone map of the London Underground network was made available in 2007.
- Isochrone Babylon. Retrieved April 5, 2012.
- "MFS ECG Potential Map (40ms)". Springer Science+Business Media. Retrieved March 21, 2012.
- Rosenbaum, David S.; Jalife, José (2001). Optical mapping of cardiac excitation and arrhythmias. Wiley-Blackwell. p. 251. ISBN 0879934816.
- Ramanathan, Charulatha; Jia, Ping; Ghanem, Raja; Ryu, Kyungmoo; Rudy, Yoram (April 2006). "Activation and repolarization of the normal human heart under complete physiological conditions". PNAS 103 (16). doi:10.1073/pnas.0601533103.
- Miyashita, T; Okano, Y (January 1995). "Isochrone map, its implication and clinical usefulness". Nihon Rinsho: Japanese Journal of Clinical Medicine 53 (1): 48–55. PMID 7897854.
- Armstrong, H. W. (September 1972). "A Network Analysis of Airport Accessibility in South Hampshire". Journal of Transport Economics and Policy 6 (3): 294–307. ISSN 0022-5258.
- "Planning for Town Centres; Practice guidance on need, impact and the sequential approach". Department for Communities and Local Government. December 2009. Retrieved March 26, 2012.
- "Transport Assessment; Guidelines for Development Proposals in Northern Ireland". Department for Regional Development. November 09, 2006. Retrieved March 26, 2012.
- "Technical Guidance on Accessibility Planning in Local Transport Plans". Local Transport Planning Network. Retrieved March 26, 2012.
- Barker, Kate (December 2006). "Barker Review of Land Use Planning". Barker Review of Land Use Planning. Retrieved March 26, 2012.
- "House-hunting goes hi-tech". The Independent. November 25, 2009. Retrieved March 22, 2012.
- Bell, V. A.; Moore, R. J. (1998). "A grid-based distributed flood forecasting model for use with weather radar data: Part 1. Formulation". Hydrology and Earth System Sciences (Copernicus Publications) 2: 265–281. doi:10.5194/hess-2-265-1998.
- Subramanya, K (2008). Engineering Hydrology. Tata McGraw-Hill. p. 298. ISBN 0070648557.
- "EN 0705 isochrone map". UNESCO. Retrieved March 21, 2012.
- "Isochrone map". Webster's Online Dictionary. Retrieved March 21, 2012.
- "Unit Hydrograph (UHG) Technical Manual". National Oceanic and Atmospheric Administration. Retrieved March 21, 2012.
- Gamper Johann; Böhlen, Michael; Cometti, Willi; Innerebner, Markus (2011). "Defining isochrones in multimodal spatial networks". Proceedings of the 20th ACM international conference on Information and knowledge management. CIKM. Glasgow. doi:10.1145/2063576.2063972. ISBN 9781450307178. Retrieved March 21, 2012.
- "Generate an isochrone map using Google Maps Api". DZone. 18 January 18, 2010. Retrieved March 21, 2012.
- Arthur, Charles (May 28, 2006). "Travel maps of Britain ... measured by time, not distance". The Guardian. Retrieved March 21, 2012.
- Street, Nicholas (June 14, 2006). "TimeContours: Using isochrone visualisation". Imperial College London. Retrieved March 21, 2012.
- Graser, Anita (February 12, 2011). "Drive Time Isochrones – An Example Using Finnish Airports". Retrieved March 22, 2012.
- "Looking for the best commuter route to Salford Quays? Stefan in Berlin can help with that". Manchester Evening News. June 07, 2011. Retrieved March 22, 2012.
- Hartley, Sarah (February 24, 2011). "Greater Manchester datastore launched". The Guardian. Retrieved March 22, 2012.
- N.B. (Jun 05, 2011). "A time-based transit map". The Economist (London). Retrieved March 22, 2012.
- O'Brien, Terrence (August 05, 2011). "Mapnificent visualizes public transportation travel time, is more exciting than it sounds". Engadget. Retrieved March 22, 2012.
- DrAlanRae (July 25, 2007). "Getting about – Isochrone map of London Underground". howtodobusiness.com. Retrieved March 21, 2012.